JPS6232742B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel phenoxyphenyl carbamate derivative, a method for producing the same, and uses thereof. For details, see the general formula (In the formula, R ₁ and R ₂ each represent a hydrogen atom, a lower alkyl group, a phenyl group, or a halogen-substituted phenyl group.), a method for producing the same, and at least one of these as an active ingredient. The present invention relates to a herbicide characterized by the following. The present invention seeks to provide novel phenoxyphenyl carbamate derivatives that are particularly useful as herbicides. The present invention also provides a method for advantageously producing a new phenoxyphenyl carbamate derivative. Furthermore, the present invention aims to provide a herbicide with particularly excellent selectivity among Poaceae genera. The present inventors have so far conducted research focusing on the fact that diphenyl ether herbicides have little phytotoxicity on rice. Compounds that do not lose
That is, as a result of searching for a new diphenyl ether compound that does not contain a nitro group, it was discovered that the compound of the present invention has many excellent characteristics as a herbicide, leading to the completion of the present invention. The phenoxyphenyl carbamate derivatives of the present invention can be advantageously produced industrially according to the following reaction formulas (1) to (3). (In the formula, R ₁ and R ₂ have the same meanings as described in the claims above, M is a hydrogen atom, a potassium atom, or a sodium atom, and X represents a chlorine atom or a bromine atom) In the above reaction formula (1), phenoxyphenol [ ] is dissolved in a suitable solvent, and an isocyanate dissolved in the same solvent, or an isocyanate and a catalyst are added thereto, and the mixture is heated at -20 to 50°C for 1 to 5 hours.
After reacting for a period of time, the solvent is removed and recrystallized by adding a small amount of solvent, or by separation using vacuum distillation or column chromatography.
The compound of the present invention [] can be obtained in good yield. Examples of the reaction solvent include benzene, toluene, ketones, ethers, and dioxane.
As a catalyst, an organic base such as triethylamine or pyridine is preferred, and as a recrystallization solvent, benzene or toluene can be used. The reaction temperature is preferably 0°C to room temperature. In reaction formula (2), the sodium salt or potassium salt [′] of phenoxyphenol is converted into isopropanol, acetone, methyl ethyl ketone, benzene,
Suspended in a solvent such as toluene or chloroform, N.N-disubstituted carbamoyl halide []
and react at -20 to 80°C for 2 to 6 hours. In this case, phenoxyphenol and N·N-disubstituted carbamoyl halide may be reacted in the same manner in the presence of a deoxidizing agent such as caustic potash, potassium carbonate, caustic soda, dimethylaniline, triethylamine or pyridine. Through the above reaction, the compound [] of the present invention can be obtained. In reaction formula (3), phenoxyphenol is converted into acetone, methyl ethyl ketone, benzene, toluene,
Alternatively, it is dissolved in chloroform, etc., and reacted with carbonyl dihalide at room temperature to obtain haloformic acid phenoxyphenyl ester [ ].
Since [] is easily decomposed by moisture in the air, it is usually not isolated, but after removing the generated hydrogen halide and excess dissolved carbonyl dihalide in the reaction solution under reduced pressure, it is reacted with twice the molar amount of amine. let After filtering off the generated hydrogen halide salt of the amine and distilling off the solvent, the compound of the present invention [] can be obtained by the same purification method as in reaction formula (1). Next, the manufacturing method of the present invention will be explained in detail with reference to Examples. Example 1 Synthesis of 3-(2-chloro-4-trifluoromethylphenoxy)phenyl N-methylcarbamate 5 g of 3-(2-chloro-4-trifluoromethylphenoxy)phenol was added to 50 ml of anhydrous benzene. Add 3 g of methyl isocyanate and 0.1 ml of triethylamine to this solution and stir at room temperature for 30 minutes.
Stir for hours. After the reaction was completed, the solvent was removed under reduced pressure to obtain an oil, which was recrystallized from a small amount of benzene to obtain 4.6 g of the desired product. Example 2 Synthesis of 3-(2-chloro-4-trifluoromethylphenoxy)phenyl N.N-dimethylcarbamate 7 g of potassium salt of 3-(2-chloro-4-trifluoromethylphenoxy)phenol was The suspension was suspended in 50 ml of methyl ethyl ketone, 4 g of dimethylcarbamic acid chloride was added thereto, and the mixture was stirred at room temperature for 1 hour. After the reaction was completed, the contents were poured into 300 ml of water and extracted with ethyl acetate. The extract phase was washed with water, dried over Glauber's salt, and then ethyl acetate was distilled off, and the residue was purified using column chromatography (silica gel, developing solvent: benzene:ethyl acetate = 50:1). n ¹⁸ . 5.8 g of the target product having _{a D} value of 1.5270 at ⁵ ° C. was obtained. Example 3 Synthesis of 3-(2-chloro-4-trifluoromethylphenoxy)phenyl N/N-diethyl carbamate Dissolve 7 g of 3-(2-chloro-4-trifluoromethylphenoxy)phenol in methyl ethyl ketone. Then, 5 g of potassium carbonate and 5 g of diethylcarbamic acid chloride were added thereto, and the mixture was stirred under heating under reflux for 5 hours. After the reaction was completed, the solid matter was filtered off with suction, methyl ethyl ketone was distilled off, and the residue was purified using column chromatography (silica gel, developing solvent: benzene:ethyl acetate = 50:1). n ¹⁸ . 4.5 g of the target product having _{a D} value of 1.5208 at ⁵ ° C. was obtained. Example 4 11 g of phosgene was absorbed in 100 ml of toluene at 20°C, 28.9 g of 3-(2-chloro-4-trifluoromethylphenoxy)phenol was added, and the liquid temperature was lowered to 20°C.
45% aqueous sodium hydroxide solution while keeping at ~25℃
After 12.5 g was added dropwise, the reaction was completed by stirring for 30 minutes. It was then washed twice with 80 ml of water and once with 100 ml of 2% sodium hydroxide. Thus obtained 3
A toluene solution of -(2-chloro-4-trifluoromethylphenoxy)phenyl chloroformate was maintained at 15 to 20°C and 12.6 g of 50% dimethylamine was added while stirring vigorously. Further, 14 ml of a 20% aqueous sodium hydroxide solution was added dropwise, and the mixture was allowed to react at the same temperature for 1 hour, and then the reaction solution was washed three times with 200 ml of cold water. The toluene layer was then dehydrated over anhydrous sodium sulfate, and the toluene was distilled off at a temperature below 60°C under reduced pressure. The remainder was subjected to column chromatography (silica gel, developing solvent; benzene: n-hexane = 1:
1) and purified by n ¹⁸ . 31.2 g of the target product having _{a D} value of 1.5270 at ⁵ ° C. was obtained. Typical compounds obtained by the above-mentioned production method of the present invention, their physical properties, and elemental analysis values are listed in Table 1 below.

【table】

[Table] The physiological properties of the compounds of the present invention as herbicides are as follows. (1) It is harmless to rice in all cultivation methods, including direct sowing, seedlings, and transplanted seedlings, even at extremely high doses, and (2) it is harmful to rice fields, including common broad-leaved weeds such as Novie, a highly harmful weed in rice fields, and Cyperaceae. It is highly effective against weeds that are conventionally difficult to control, such as Japanese firefly and Japanese cypress. (3) Applicable periods such as pre-planting treatment of paddy rice, treatment immediately after rice transplantation, and treatment during the growing season of rice and weeds more than 10 days after transplantation. (4) Not only does it have soil treatment ability against field weeds such as pigweed, crabgrass, blueberry, leafminer, sparrowgrass, and hartade, but also has excellent stem and leaves (aerial parts) in dry field direct sowing and upland rice cultivation.
Has processing power. (5) The effect is difficult to reduce even in reducing soil when raw straw is applied. As mentioned above, the compound of the present invention has the ability to treat foliage (aerial parts) in dry field direct sowing and upland rice cultivation, is effective against almost all weeds, and is surprisingly harmless to the genus Poaceae of the Poaceae family. Indicates selection among genera of the Poaceae family (in the Poaceae family, only the genus Poaceae is harmless, while the genera Wheat, Poaceae, Novieum, Maize, etc. are withered or severely damaged). The phytotoxic symptoms exhibited when treated with the compound of the present invention strongly inhibit cell division and elongation at the growth point of grasses other than rice. Regardless of whether the compound is treated with foliage or soil, the compound of the present invention is absorbed through the young shoots or roots and then exposed to sunlight. The drug of the present invention can be used not only in rice fields and upland fields as described above, but also in orchards, mulberry orchards, mountain forests, and other non-agricultural lands, and has a wide range of applications. The method of using the agent of the present invention generally follows that of conventional herbicides. That is, although it differs depending on the target plant, etc., generally, a method using flooded or non-flooded soil treatment or whole foliage treatment is appropriate. The application concentration (application amount) of the compound represented by the above general formula, which is the active ingredient of the herbicide of the present invention, varies depending on the target plant, but generally it may be used in the range of 3 g to 50 g/are. When using the herbicide of the present invention, it can be mixed with various carriers depending on the usage situation, and used as a powder, granule, tablet, wettable powder, emulsion, etc., for example. The carrier referred to herein may be either solid or liquid, or a combination thereof. Examples include mineral powders such as kaolinite, bentonite, pyrofluorite, talc, diatomaceous earth, silica gel, calcium carbonate, and slaked lime, starch, vegetable powders such as gum arabic, alcohols, ketones, These include organic solvents such as kerosene, benzene, toluene, xylene, cyclohexane, methylnaphthalene, dioxane, dimethylformamide, dimethyl sulfoxide, corn oil, o-dichlorobenzene, and isophorone, as well as auxiliaries used in the formulation of agricultural chemicals. agents, such as wetting agents,
A dispersant, a fixing agent, a spreading agent, etc. may be used as appropriate. Any of the preparations can not only be used alone, but also be mixed with fungicides, nematicides, insecticides, plant growth regulators, etc., or mixed with other herbicides, and even May be used in combination with fertilizer. Next, typical formulation examples of the herbicide of the present invention will be shown in Examples. Compounds are represented by compound numbers in Table 1 above. "Parts" are expressed as "parts by weight." Example 5 Compound No. 1 20 parts Talc 80 parts These were thoroughly ground and mixed in a ball mill to form a powder. Example 6 Compound No. 2 7 parts Bentonite 88 parts Sodium lignososulfonate 5 parts A small amount of water was added to these and granulated to obtain granules. Example 7 Compound No. 4 50 parts bentonite 45 parts polyoxyethylene alkylaryl ether
5 parts These were mixed and ground to obtain a 50% wettable powder. Next, the effects of the compounds of the present invention will be explained using test examples. The numerical values in the table for each test example below indicate the degree of crop damage and weed damage, and are specifically as follows.

【table】

[Table] Test example 1 (Flooded soil capacity test) Fill a 1/10000-acre pot with paddy soil, sow wildflowers, Japanese grass, Japanese chickweed, and firefly, and flood to a depth of 3 cm. When weeds germinate, drop the following active ingredients at the specified concentration using a pipette. The degree of weed control ability was observed on the 20th day after the chemical application. The results are shown in Table 2. The compounds are indicated by compound numbers in Table 1 above. (Same below)

【table】

【table】

[Table] Test Example 2 The following plants were used as test plants and tested in the following manner. Fill a 1/10000 are pot with paddy soil. For rice, seeds are sown directly (abbreviated as "direct sowing" in the table), rice seedlings at the two-leaf stage are transplanted to a depth of 2 to 4 cm from the soil surface (transplanting), or the roots are fixed to the soil surface without transplanting ( Three methods of seedling sowing were used. In addition, annual broad-leaved weeds such as chickweed, azalea, and chinensis were mixed into the soil surface layer of 1 cm. Furthermore, we used a method of transplanting the Japanese cypress and Japanese cypress. After sowing or transplanting the above pots,
Flooded to cm. At the time of weed germination, a predetermined concentration of the active ingredient is dropped with a pipette. On the 20th day after spraying, the damage to rice and the degree of weed control ability were observed. 3rd result
Shown in the table.

[Table] Test example 3 The same test plants as in test example 2 were prepared, and the
The prescribed concentration of chemicals was applied at the 2.5 leaf stage, ie, 15 days after rice transplantation. 20 days after application, the degree of chemical damage to rice and weed control ability was observed. The results are shown in Table 4.

[Table] Test Example 4 Using the same test weeds as in Test Example 2, the weeds were sown or transplanted, and immediately after being flooded with water, the active ingredient at a predetermined concentration was applied. Three days later, the rice seedlings were transplanted to a depth of 2 cm below the soil surface. On the 20th day after chemical treatment, rice damage and weed control ability were observed. The results are shown in Table 5.

[Table] Test Example 5 (Upland soil treatment test) Rice, wheat, radish, and soybean were used as the test crops, and crabgrass, Japanese radish, and soybean were used as weed plants.
Upland soil containing the seeds of Cucumber and Hurtade was filled into clay pots and treated with the following compounds at the concentrations listed below. Thirty days after the treatment, the phytotoxicity and weed control ability of the test crops were observed. The results are shown in Table 6.

[Table] Test Example 6 (Stem-leaf contact toxicity test) Fill a 1/10,000 are pot with field soil, sow seeds of the following test plants, and cover with 1 cm of soil. After germination of these seeds, 1 ml of a diluted solution of the active ingredient wettable powder at a predetermined concentration was sprayed over the entire surface at the 1st to 2nd true leaf stage for radish and at the 2nd to 3rd true leaf stage for wheat. The degree of phytotoxicity of the test plants was observed on the 15th day after the treatment. The results are shown in Table 7.

[Table] Test Example 7 A foliage contact toxicity test was conducted in the same manner as in Test Example 6 using the following plants. The degree of phytotoxicity of the test plants was observed on the 15th day after the chemical treatment. The results are shown in Table 8.

【table】

Claims (1)

[Claims] 1. General formula (In the formula, R ₁ and R ₂ each represent a hydrogen atom, a lower alkyl group, a phenyl group, or a halogen-substituted phenyl group.) 2. The compound according to claim _{1, wherein R 1} is a hydrogen atom and R ₂ is a methyl group. 3. The compound according to claim ₁ , wherein R 1 is a hydrogen atom and R ₂ is an ethyl group. 4. The compound according to claim 1, wherein R ₁ is a hydrogen atom and R ₂ is an n-propyl group. 5. The compound according to claim 1, wherein R ₁ is a hydrogen atom and R ₂ is an i-propyl group. 6. The compound according to claim ₁ , wherein R 1 is a hydrogen atom and R ₂ is a t-butyl group. 7. The compound according to claim 1, wherein R ₁ and R ₂ are methyl groups. 8. The compound according to claim 1, wherein R ₁ and R ₂ are ethyl groups. 9. The compound according to claim ₁ , wherein R 1 is a hydrogen atom and R ₂ is a phenyl group. 10. The compound according to claim ₁ , wherein R 1 is a hydrogen atom and R ₂ is a 3'-chlorophenyl group. 11. The compound according to claim ₁ , wherein R 1 is a hydrogen atom and R ₂ is a 3',4'-dichlorophenyl group. 12 R ₁ is a hydrogen atom and R ₂ is a hydrogen atom or n-
The compound according to claim 1, which is a butyl group. 13. The compound according to claim ₁ , wherein R 1 is a methyl group and R ₂ is an ethyl or n-butyl group. 14. The compound according to claim 1, wherein R ₁ and R ₂ are i-propyl groups. 15 3-(2-chloro-4-trifluoromethylphenoxy)phenol represented by the general formula R ₂ -NCO (wherein R ₂ represents a lower alkyl group, phenyl group or halogen-substituted phenyl group) General formula characterized by reacting with isocyanate A method for producing a compound represented by the formula (wherein R ₂ has the same meaning as above). 16 3-(2-chloro-4-trifluoromethylphenoxy)phenol or its alkali metal salt and general formula (In the formula, R ₁ and R ₂ are a hydrogen atom, a lower alkyl group, a phenyl group, or a halogen-substituted phenyl group, respectively, and X is a chlorine atom or a bromine atom.) general formula to A method for producing a compound represented by the formula (wherein R ₁ and R ₂ have the same meanings as above). 17 Haloformic acid 3-(2-chloro-4-trifluoromethylphenoxy) phenyl ester and general formula (In the formula, R ₁ and R ₂ each represent a hydrogen atom, a lower alkyl group, a phenyl group, or a halogen-substituted phenyl group.) A method for producing a compound represented by the formula (wherein R ₁ and R ₂ have the same meanings as above). 18 General formula (In the formula, R ₁ and R ₂ are a hydrogen atom, a lower alkyl group, a phenyl group, or a halogen-substituted phenyl group.) Containing at least one type of carbamic acid phenoxy phenyl ester derivative as an active ingredient. A herbicide characterized by 19. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is a methyl group. 20. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is an ethyl group. 21. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is an n-propyl group. 22. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is an i-propyl group. 23. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is a t-butyl group. 24. The herbicide according to claim 18, wherein R ₁ and R ₂ are methyl groups. 25. The herbicide according to claim 18, wherein R ₁ and R ₂ are ethyl groups. 26. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is a phenyl group. 27. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is a 3'-chlorophenyl group. 28. The herbicide according to claim 18, wherein R ₁ is a hydrogen atom and R ₂ is a 3',4'-dichlorophenyl group. 29 R ₁ is a hydrogen atom and R ₂ is a hydrogen atom or n-
The herbicide according to claim 18, which is a butyl group. 30. The herbicide according to claim 18, wherein R ₁ is a methyl group and R ₂ is an ethyl or n-butyl group. 31. The herbicide according to claim 18, wherein R ₁ and R ₂ are i-propyl groups.